Abstract: A cast bus bar clamp with perimetric ribs and a connecting web is provided. The design eliminates abrupt changes in cross-sectional area. This, in turn, provides a less abrupt temperature gradient on cooling which, in turn, minimizes nonuniform solidification which, if present, frequently causes the formation of weakening cracks. To improve the distribution of clamping pressure, the clamp is usually given a convex curvature so that when the clamp is tightened there are five pressure points. The design provides an improved strength-to-weight ratio and a more reliable and economical structure.

Abstract: Method and apparatus for detecting the presence of flat wheels on railroad cars, comprising an electro-acoustic transducer located on the track wayside so as to pick up the vibrations generated by a passing train. If a flat wheel is present it will generate a periodic clanging sound at a frequency proportional to train speed and wheel diameter. The invention capitalizes particularly on the measurement of train speed to control the response of an adaptive filter so as to enhance the periodic clanging frequency with respect to the background noise, thereby to improve the signal-to-noise ratio; the enhanced signal is further autocorrelated for ten wheel revolutions and if a periodic signal is present in the narrow frequency band of interest, a large periodic autocorrelation output will result and, as a consequence, any wheel flat will be readily detected and will act to trigger an alarm to alert the train crew of the condition.

Abstract: A solid state code transmitter adapted for use with a conventional local fire alarm system in connection with installations that include a McCulloh loop circuit for the transmission of signals to a central proprietary fire alarm surveillance point. The transmitter circuit generates an electronic data word 17 bits long, the first 14 bits being field programmable by way of miniature DIP switches, each data word representing an equivalent of one round of generated code.

Abstract: There is disclosed a circuit for energizing a vital relay in response to an input signal that is modulated between two frequencies. A discriminator circuit responds to the modulated frequencies and alternately produces an output patented of one polarity and then a reverse polarity in response to the modulated signals. Coupled between the discriminator and the vital relay is a relay driver which responds to the output of the discriminator and energizes the vital relay. A d.c. power supply is coupled to the relay driver. The vital relay includes two windings. Failure of the modulation, the d.c. source or virtually any circuit element, will result in release of the vital relay. The disclosed embodiment uses photoresistors as switching elements.

Abstract: A selected predetermined coded alarm is provided indicative of the one of a plurality of leads on which a signal indicative of an alarm condition may appear. If a station coded alarm should be initiated during the transmission of a coded alarm, the coded alarm is immediately terminated and the station coded alarm is given priority and transmitted immediately. Upon completion of the station coded alarm, the coded alarm being transmitted at the time of the receipt of the station coded alarm is transmitted with the new transmission starting at the start of its code irrespective of the status of the transmission at the time of the interruption. Appropriate delays are provided between codes and code elements. The plurality of leads are sequentially scanned, but once a transmitted code is transmitted, it is not retransmitted on a subsequent scan unless a reset signal has been provided. Each transmitted code is repeated a predetermined number of times.

Abstract: A locking system featuring a movable pin which is selectively operative to lock a blender jar into its holder when the entire jar assembly is positioned on a console or the like for performing a blending operation; otherwise the pin stays in an appropriate position such that the blender jar can be screwed into its holder without hindrance.

Abstract: Apparatus is provided for modifying a conventional target locating system in which targets respond to an interrogation signal by transmitting a reply, and the target location is deduced from the azimuth from which a reply is received and the delay between the interrogation signal and the reply. The improvement includes a controllable attenuator coupling the receiving antenna to the target locating system which is controlled to selectively discriminate against selected range cells at selected azimuths. In a preferred embodiment, digital circuitry is relied upon to control the attenuator, and the identication of the range cells to be discriminated against is stored in a digital memory.

Abstract: A fail-safe solid state logic system based on the use of an AC input signal of one type, and a DC input which causes a logical gate to convert the AC input signal to a totally different AC output signal; that is, to one adapted to be received by a vital driver or the like, which is tuned to accept only that different AC output signal and no other. Accordingly, the failures which are most likely to occur, namely, shorts from input to output or failure to toggle, result in the AC signal frequency not being changed and as a consequence, the system fails safe.

Abstract: A selectively adjustable air deflecting damper is provided in the air exhaust barrel of an electrically heated hand-held hair drier for adjusting the area of the air discharge orifice and concomitantly the air velocity of the heated air discharge. The damper is pivoted in the barrel downstream of the air heating element and is selectively movable between first and second positions providing maximum and minimum effective orifice openings for producing a dispersed and a concentrated air flow, respectively. The damper is spring biased to its first position and operated by a trigger arranged for actuation by a digit of the hand holding the hair drier during use.

Abstract: Apparatus for automatically calibrating smoke detectors within desired ranges of values of smoke obscuration, and thereafter retesting them for valid calibration; in accomplishing this the smoke obscuration is continuously increased at a predetermined uniform rate.

Abstract: In some circumstances it is important to maintain a d.c. potential within a specific range of a critical value. The circuit shown will provide a fail-safe signal if the potential deviates from the allowed range. Two zener diodes and two optically coupled isolators are used. If the d.c. potential remains within the critical range, an a.c. test signal back biases one optically coupled isolator and forward biases the other on the positive half cycle; and on the negative half cycle back biases the other and forward biases the one. Thus the two optically coupled isolators conduct on alternate half cycles of the a.c. test signal. If the d.c. potential strays from the required range, the optically coupled isolators stop alternate conduction and a fail signal is given. If either zener diode should fail in a mode which alters its characteristics so that the circuit would fail to detect a voltage excursion outside the allowed range, a fail signal is given.

Abstract: A liquid tight connector for joining a liquid tight flexible conduit to a junction box or panel and having improved ground continuity is provided. The connector includes a body member having a cast-on lug to which an external ground may be secured. To provide a liquid tight seal between the fitting and the junction box, channel or raceway, an O-ring or similar seal is provided. The O-ring is placed in a recess whose depth and cross section are so related to the size and characteristics of the O-ring, that when the O-ring provides a liquid tight seal, a metallic surface of the body is in contact with the joined metallic member. With this increased metallic contact, there is an improved capacity to conduct fault current. The recess may be positioned to provide substantial contact area on an appropriate side of the perimeter of the O-ring. This protects the contact area from rust and/or corrosion which would reduce the fault current carrying capacity.

Abstract: One or more radially projecting tabs are provided on a discontinuous ring for retaining the ring in proper association with a body member in spite of movement or vibration of the assembly. The tab, or tabs, mate with a grooved section of the body member. The groove may comprise a thread. The ring may be internal or external to the body member. The retaining tab will project radially outward or inward when the ring is to be internal or external, respectively, to the body member. The tabs have an axial thickness of the order of 25 percent, or less that of the ring. To provide secondary internal retaining means, a portion of the ring may be cut from an oversize ring so that a stress is formed when the ring is closed for inserting the ring in an internal opening. When a ring is to be used external to a body member, a simple cut may be made in an undersize ring so that a stress is formed when the ring is opened for placement external to the body member.

Abstract: A track circuit signalling system for an electrified rapid transit system using significantly fewer components is provided. Instead of a transmitter and receiver at each track circuit boundary, alternate boundaries have transmitters only; and the intermediate boundaries have two receivers. The coupling units for the two receivers are more economical than the prior art coupling unit for coupling the transmitter-receiver combination. The transmitters on each side of a receiver pair transmit signals on different carrier frequencies. Each transmitter transmits in both directions from its location. Of the two receivers at a given boundary, one is tuned to respond to signals from the transmitter on one side, while the other receiver of the pair is tuned to respond to signals from the transmitter on the other side. For special applications using overlapping track circuits, selected transmitters may be omitted and a single receiver used on each side of the omitted transmitter.

Abstract: A monitoring device which is directed to achieving a more reliable power supply for an electronic or electromechanical system; such monitoring device including a means for selecting, in response to detection of subtle failures in either of two power supplies, so as to connect one and only one of the power supplies, regardless of internal failure within the monitoring device itself.

Abstract: An overlay selective harmonic transducer device is installed on affected track circuits, that is, track circuits on which interference with normal functioning has occurred due to traction power harmonics.

Abstract: A dynamic loudspeaker is driven by chopped d.c. from the collector of a transistor. A free wheeling diode is connected in parallel with the speaker circuit to dissipate the inductive energy in the speaker voice coil when the transistor is turned off. The transistor is controlled by a voltage controlled oscillator which, under control of other elements, can be made to produce a wide variety of cyclically varying output signals for producing a wide range of sounds, tones and signals from the loudspeaker. This permits selection of a tone which differs sufficiently from the ambient noise to assure attracting attention. By the use of chopped d.c. to drive the speaker, the expense, weight and bulk of an impedance matching transformer is eliminated. A plurality of individually operable switches are provided for switching circuit elements in and out of circuit to modify wave shapes and alter sound output.

Abstract: Penetrations or passageways through fire rated or fire resistant walls, floors, partitions, and ceilings are frequently necessary to provide for present or future pipes, cables or conduits. A fitting placed in the penetration provides a seal to prevent the passing of fire, products of combustion, gas vapor or liquid through the penetration under normal conditions and under adverse conditions of fire or elevated temperatures. The fitting includes an elastomeric-like material, under pressure, which provides the initial barrier. An intumescent material, which responds to heat is provided to expand and fill any void created by the degeneration of the elastomeric material in response to the heat or fire. The fitting may include an outer exposed layer of intumescent material to serve as an insulator.

Abstract: Apparatus for detecting the presence of flat wheels on railroad cars, comprising a high frequency transmitter or source connected so that the rail feed points are staggered or offset with respect to the detector apparatus. As a result, the transmitter cannot be completely shorted by a wheel axle; also, the stagger arrangement permits the overlap of two test sections so that no part of the wheel circumference is missed by the detector. Also the use of current detection of the transmitted signal minimizes loading effects on the received signal by adjacent wheel axle sets.